As a screen rendering and updating method for information terminals such as personal computers, tablets, smart phones, and kiosk terminals, technology that detects the gaze of a user and switches display content on the screen or performs a scroll operation in accordance with the gaze movement is available. Specifically, display on the screen is switched or the screen is scrolled after determining whether a specific area or the like has been read, thereby moderating the operation burden on the user.
In addition, the following technology that performs gaze-based screen control or the like is available. That is, a determination area is provided on an object for reading, such as text, content or the like. In the case where the coordinates of the gaze of a user are detected in that determination area, it is determined that the user is referring to that determination area. In the case where the order of parts to which the user has referred matches a predetermined order, it is determined that the user has read the object for reading, and gaze-based screen control or the like is performed.